The railway route across the Bernina pass, listed in the UNESCO world heritage is the highest transalpine railway link and one of the steepest adhesion railways in the world with a 7 percent incline. ABB supplied an innovative and energy-efficient multi-system drive packages developed specifically for the high demands of the Rhaetian Railway line, for operation under direct current (1 kV) on the Bernina line and with alternating current (11 kV) on the remaining rail network.
The multi-system drive package needed to be extremely powerful and rugged as well as highly reliable under harsh winter conditions. For these narrow gauge trains, ABB developed under-floor mounted Compact Converters that comprise two 350 kW propulsion converters, galvanically insulated auxiliary converters and a battery charger, all in one very robust housing.
Each multi-system train is equipped with four BORDLINE Compact Converters and two under-floor traction transformers – LOT1250.
Average high temperatures between November and March are below freezing and overhead lines, or catenaries, supplying electricity to trains can grow a thick coat of ice. The traction system relies on sophisticated software that recognizes when ice is building up, automatically react to create an artificial arc, keeping electricity flowing and vaporizing any ice left on the wires.